Refrigerating apparatus, including a lubricant cooler



July 19, 1949. L. A. PHILIPP 2,476,764

REFRIGERATING APPARATUS, INCLUDING 4 A LUBRICANT COOLER Filed Feb. 7,1947 FIE-.7

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v INVENTOR. L nweavce' 9 lQYIL/FP BY M TTOR/wry Patented July 19, 1949REFRrGERA'rING APPARATUS, INCLUDING A LUBRICANT COOLER Lawrence A.Philipp, Detroit, Mich., assignor to Nash-Kelvinator Corporation,Detroit, Mich, a corporation of Maryland 1 'Application February 7,1947, Serial No. 726,999

7 Claims. ((152-115) This invention relates to refrigerating apparatusand more particularly to the removal of heat from motor compressor unitsused in such apparatus.

One of the objects of my invention is to pro-' vide an improved"arrangement for removing heat from a motor compressor unit.

Another object of my invention is to circulate the lubricant used for acompressor unit through a cooler by the action of the compressor to coolthe lubricant and thereby remove heat from the compressor.

Another object of my invention is to provide in a refrigerating systemof the compression type an improved arrangement for dissipating the heatof the compressing mechanism by circulating the lubricant for saidmechanism through a lubricant cooler by utilizing theaction of saidmechanism and the velocity of the gas to be compressed to promote theflow of said lubricant therethrough.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

In the dawings:

Fig. 1 is a side view in elevation of my invention showing my improvedmotor compressor with the lubricant cooling arrangement and showingdiagrammatically a condenser and evaporator connected thereto;

Fig. 2 is a top view in elevation of the motor compressor arrangementshown in Figure 1;

Fig. 3 is a fragmentary view taken alon the line 3-3 of Figure 1',

Fig. 4 is a fragmentary view taken along the line t-B of Figure handFig. 5 is a fragmentary view taken along the line 55 of Figure 1.

Referring to the drawings, .the numeral 29 designates in generalarefrigeratingjsystem which includes a motor compressor unit'22,condenser 24 and evaporator 23.

The motor compressor unit 22 includes a sealed casing 30 which providesa reservoir in the lower part thereof for lubricant, the level of whichis at 32. The casing to encloses a compressor it which is driven by anelectric motor 42. The motor and compressor may be of any suitabledesign of the type well known in the art.

The compressor 40 has its inlet in open communication with the interiorof the casing 30 and takes in gas to be compressed from the interior ofthe casing above the level of lubricant.

The compressor compresses the gas and delivers it through its outletdirectly into a conduit 5ll whence the gas is conducted through conduit50 into condenser 24 wherein it is liquified and from where it isdelivered to evaporator 26 under the control of a small diameter tube54. The refrigerant in the evaporator is evaporated and is thenwithdrawn through conduit 56 by the compressor whence the gas flo s intothe interior of casing 30 and the cycle is completed.

In the compressing operation considerable heat is produced within thecasing and to aid in dissipating this heat the warin lubricant iscirculated outside of casing 30 through a lubricant cooler 60 by theaction of the compressor. The cooler 60 includes a conduit 82 havingfins 64 to increase the effectiveness of the cooler.

The cooler fill is connected on its inlet end to the casing 30 by afitting 66 near the lower part of the lubricant reservoir below thelevel of lu bricant therein. The cooler surrounds the casin 30 with thecoolei outlet end being above fitting 66 and connected to the casing 30by a fitting l0 positioned just below the level of lubricant. Due to thegravity head of the lubricant the lubricant will flow into the coolerand completely fill it and fittings 66 and '50 with lubricant.

As will be noted, the outlet end of conduit 56 terminates in fitting Hi.Accordingly the gas leaving conduit 56 flows into the lubricant infitting iii and into the upper level of the lubricant in casing 30.During operation of the compressor the gas leaving the outlet of conduit56 will enter fitting i0 and due to the velocity of the gas the gas willblow some of the lubricant out of fitting W and some of the upper levelof lubricant away from fitting 19 toward the interior of the casing 3t.When this takes place the gravity head of the lubricant will causeadditional lubricant to enter fitting 66 whence it will flow upwardlythrough cooler 60 into fitting l0 and upper level of lubricant in casing30 to replace the lubricant blown away by the action of the compressorand velocity of gas to be compressed. Thus a continuous flow oflubricant in cooler 60 is promoted during operation of the compressor.In flowing through the cooler the heat of the lubricant is beingdissipated in the environment air thus removing considerable heat fromthe interior of the casing and compressor which is immersed in thelubricant in casing 30.

From the foregoing it will be noted that I have provided for dissipatingthe heat of a motor compressor unit by utilizing the action of thecompressor for conducting a quantity of lubricant outside of the casingwhich houses the motor compressor unit to thereby dissipate the heat ofcompression in the environment air surrounding the motor compressorunit. Since the unit is immersed in the lubricant and the lubricant isutilized to lubricate the compressor considerable heat is conducted tothe lubricant, and by circulating the lubricant outside of the casingwhich houses the motor compressor unit where the circulating environmentair cools the circulating lubricant an effective arrangement is providedfor dissipating the heat of the motor compressor unit.

Although only a preferred. form of the invention has been illustrated,and that form described in detail, it will be apparent to those skilledin the art that various modifications may be made therein withoutdeparting from the spirit of the invention or from the scope of theappended claims.

I claim:

1. Refrigerating apparatus comprising a casing, lubricant in saidcasing, a motor compressor unit in said casing, a condenser connected tosaid compressor, a refrigerant evaporator connected to said condenser, alubricant cooling conduit located outside said casing and having bothends connected in open communication with the interior of said casingbelow the level of lubricant in said casing to receive lubricant in saidlubricant cooling conduit and a conduit connecting the outlet of saidevaporator with one end of the lubricant conduit so that the gas to becompressed must flow through some of the lubricant in the lubricantconduit before reaching the inlet of the compressor to cause lubricantto flow through said lubricant cooling conduit.

2. Refrigerating apparatus comprising a casing, lubricant in saidcasing, a compressor in said casing, a cooler for said lubricant locatedoutside of said casing but connected in open communication with thelubricant in said casing and an intake conduit for gas to be compressedpositioned in the upper part of said cooler to direct said gas throughthe lubricant in the upp r part of said cooler before it is compressedto cause lubricant to circulate from said casing through said cooler.

' 3. Refrigerating apparatus comprising a casing, lubricant in saidcasing, a compressor in said casing, a refrigerant condenser, arefrigerant evaporator, a lubricant cooler positioned outside of saidcasing in open communication with said lubricant in said casing, conduitmeans for conducting refrigerant to and from the condenser andevaporator respectively under the action of the compressor with one endof said conduit means being connected to said cooler to causerefrigerant ,to flow through said cooler to promote the flow oflubricant therethrough.

4. Refrigerating apparatus comprising a casing, lubricant in saidcasing, a lubricant cooler having its outlet end connected to saidcasing below the level of lubricant therein and being positioned 4outside of said casing, a compressor in said casing refrigerant conduitmeans positioned with its outlet end arranged to discharge refrigerantin said lubricant at the outlet end of said cooler to thereby utilizethe action of said compressor and the velocity of refrigerant gas toblow lubricant away from the outlet of said cooler to allow morelubricant to enter the inlet end of the cooler and to flow through thecooler to replace the lubricant blown away by the gas to thus promotethe circulation of lubricant through the cooler.

5. Refrigerating apparatus comprising a casing, lubricant in saidcasing, a lubricant cooler positioned outside said casing with its inletand outlet ends connected to said casing below the level of 'lubricanttherein, a refrigerant conduit having its outlet end positioned in saidlubricant at the outlet end of said cooler for discharging refrigerantinto said lubricant and into the interior of said casing and acompressor in said casing for causing refrigerant to flow through saidrefrigerant conduit.

6. In refrigerating apparatus having a refrig' erant evaporator, acasing having a refrigerant inlet, a refrigerant return conduitconnecting said evaporator and said refrigerant inlet, a refrigerantcompressor within said casing having an outlet connected to saidevaporator and having a suction inlet in communication with said casinginlet, lubricant in said casing having a liqud level above sad casinginlet, and means forming a lubricant cooling passage externally of saidcasing having an outlet end connected to said casing below said casinginlet and having an inlet connected to said casing inlet anterior to thedischarge end of said return conduit.

'7. In refrigerating apparatus having a refrigerant evaporator, a casinghaving a refrigerant inlet, a refrigerant return conduit connecting saidevaporator and said inlet, a refrigerant compressor within said casinghaving a suction inlet communicating therethrough with said casing inletand having an outlet for connection to the evaporator, lubricant withinsaid casing for lubricating said compressor and having a liquid levelabove said casing inlet, a lubricant outlet in said casing below saidcasing inlet, a lubricant cooling coll mounted on and extending aroundsaid casing having one end connected to said casing outlet. and anaspirator tube receiving the discharge end of said return conduit andthe other end of said cooling coil and being connected to said casinginlet.

LAWRENCE A. PHILIPP.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PA'I'ENTS Number Name Date 1,958,087 Hofiman May 8, 19342,178,425 Johnson Oct. 31, 1939

